The present invention relates generally to semiconductor wafer processing systems and devices. The present invention also relates to over head transport (OHT) systems and devices utilized in semiconductor wafer processing operations. The present invention additionally relates to door opener and load ports thereof utilized in semiconductor wafer processing operations. In addition, the present invention relates to devices and methods for adjusting and calibrating such load ports.
The fabrication of electronic devices on substrates is typically performed utilizing semiconductor processing devices and systems. Such semiconductor processing devices and systems can take on various implementations, including single wafer systems and batch type systems. Single wafer systems or devices involve the processing of a single wafer in a processing chamber. Batch type systems or devices involve the processing of multiple wafers in a chamber apparatus. Despite system or device architecture disparities, substrates are generally delivered to the processing systems from a clean room utilizing standardized interfaces and wafer pods or cassettes.
Such systems are commonly utilized in the semiconductor manufacturing industry. Such systems may be entirely automated or may include human interaction. The level of human interaction with such systems can be a contributing factor to costs involved in the overall semiconductor fabrication process. In most systems, a human operator or factory automation can deliver multiple wafers loaded in wafer pods or cassettes to a loading mechanism which transfers the wafers from the clean room in a fabrication facility into the processing system without exposing the wafers to contaminants. The delivery of wafers between processing systems and the operation of pod doors has been standardized by an organization known as SEMI.
Recent advances in circuit design and processing technology have driven a significant decrease in the size of semiconductor devices. At the same time, chip makers are trying to increase the number of devices, which can be produced on a single wafer. Accordingly, wafer sizes have increased to 300 mm, thereby requiring larger systems, which increase the amount of fabrication facility floor space required to house the larger systems. Also, as the wafer size has increased, the handling of wafers has become more limited to factory automation, instead of manual handling, to accommodate the increase in size and weight of wafer pods.
FIG. 1 is a schematic top view of a representative prior art processing system 10 having a front-end staging area 12, which mounts a plurality of wafer pod loading stations 14 through an interface wall 16 separating the clean room 18 from the gray area 20 where the processing system 10 is housed. A single wafer processing system may include one or more load lock chambers 22, a central transfer chamber 24 and a plurality of processing chambers 26 mounted on the transfer chamber.
A robot 28 disposed in the front-end staging area 12 moves wafers from wafer pods disposed on the pod loading stations 14 into a load lock chamber 22. A robot 30 disposed in the transfer chamber 24 moves wafers from a load lock chamber 22 into a processing chamber 26. The pod loading stations 14 are generally disposed through an opening in the interface wall 16 and provide a movable door opener 32, which can seal the opening in the interface wall 16 when a wafer pod is not positioned on the pod loading station 14. An example of a movable door opener currently in use is the Applied Materials Door Opener (ADO) manufactured by Applied Materials, Inc. of Santa Clara, Calif. Note that the configuration depicted in FIG. 1 is presented herein for illustrative purposes only and is not considered a limiting feature of the present invention.
There are several commercial pod loading stations available from manufacturers, such as Jenoptik/INFAB, ASYST, PRI Automation and DYFUKU. These pod loading stations are very similar in function and appearance as they are all designed to meet applicable SEMI standards for the interface to the processing system as well as the interface to the pod and the pod loading station as presented to the fabrication facility material transport system (AGV, OHT, PGV). These current designs share the following details: a mechanical interface to receive a pod using three pins as required by SEMI; a mechanism to latch the pod into place on the pod loader; a mechanism to grip a pod door and operate the pod door latch mechanism; and, a mechanism to remove the pod door and store the door out of the way of the pod opening to allow clear access to the wafers stored inside the pod. These existing designs all generally employ a mechanical motion, which latches the pod to a fixed position, grips and unlatches the pod door, pulls the pod door horizontally away from the pod (i.e., into the staging area 12), and then lowers the pod door below the plane of the pod for storage of the door while allowing access to all wafer positions. The pod loading stations 14 are designed so that an operator or factory automation can deliver a wafer pod onto the pod loading station and the wafers can be unloaded into the semiconductor wafer processing system.
Based on the foregoing, it can be appreciated that in most over head transport (OHT) systems, SEMI standards must be met, including height, leveling, side-to-side, and front-to-back positioning. One of the problems with current OHT systems thus involves positioning. The ADO load port, for example, has a very rough, and simple mechanism for adjusting position, and also has few tolerances to adjusting the height and leveling position. In addition, such an ADO mechanism is difficult for adjusting the load port position. Fine tuning of the load port position can not be achieved. Calibration of such ADO mechanisms generally requires a great deal of time to calibrate the load port position. Additionally, the ADO mechanism requires at least two individuals to calibrate the load port position.
The present inventors have thus concluded that a need exists for a new mechanism, including a method thereof, for fine tuning the load port position. A precise and xe2x80x9csmartxe2x80x9d load port adjusting mechanism is thus required, including one that can handle larger tolerances for load port adjustments. In addition, it would be desirable to implement a load port adjusting mechanism that requires only one person to perform the adjustment and which also saves calibration time. The present inventors have overcome the drawbacks associated with prior art devices, such as the ADO mechanism by presenting an improved load port adjusting mechanism including a method thereof, which is disclosed and described herein.
The following summary of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention, and is not intended to be a full description. A full appreciation of the various aspects of the invention can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
It is therefore one aspect of the present invention to provide an improved semiconductor wafer processing apparatus and method.
It is yet another aspect of the present invention to provide an improved load port utilizing in semiconductor wafer processing operations.
It is still another aspect of the present invention to provide a calibration mechanism for load port adjustment.
It is also an aspect of the present invention to provide an improved calibration mechanism for fine tuning the position of a load port, including the height level, side-to-side and front-to-back positions of the load port.
The above and other aspects of the present invention can thus be achieved as is now described. An apparatus and method for adjusting the position of a load port utilized in a semiconductor wafer processing system is described herein. Generally, a door opener can be configured for opening a door through which a semiconductor wafer may enter for subsequent positioning and processing thereof by a semiconductor wafer processing system. A load port is associated with the door opener. A calibration mechanism can then be utilized for calibrating the load port for leveling and height positioning, such that a plurality of directional axis associated with the load port do not interfere with one another, thereby conserving calibration time while permitting a single individual to perform calibration operations thereof.
Such directional axis associated with the load port comprise a Y-axis and a Z-axis. The calibration mechanism thus comprises an adjusting mechanism for fine tuning one or more positions of the load port. The calibration mechanism comprises a screw assembly, and a receiver for receiving the screw assembly, wherein the receiving area forms a slot through which the screw assembly may move, such that the screw assembly moves through the slot to assist in a calibration of the load port by the calibration mechanism. The screw assembly can be configured to include a top screw associated with the screw assembly, wherein the top screw is utilized to pull or push the screw assembly from or into the slot. A plurality of walls may form at least two additional slots, which limit the sliding of the screw assembly into such additional slots. Also, at least two linkages are generally connected to the screw assembly, wherein the linkages transfer force to the load port during a side-to-side calibration of the load port by the calibration mechanism.
The calibration mechanism can be configured to generally include a y-directional screw bar surrounded by a cover, and a ball-pillar connected to the y-directional screw bar. The calibration mechanism also can includes a plurality of walls forming at least one slide slot, a z-directional screw bar integrated surrounded by a sleeve thereof, a screw connected to at least one slide located within slide slot, and at least one linkage connecting the z-directional screw bar to the slide. The semiconductor wafer processing system comprises an over head transport (OHT) system. The calibration mechanism generally comprises an adjusting mechanism for adjusting a height and a level of the load port, wherein the load port is associated with the OHT system.